Backed by nearly half of the Senate’s Democrats, Sen. Bernie Sanders (I-Vt.) and Sen. Patty Murray (D-Wa.) are introducing revamped legislation to raise the minimum wage to $15 and index it to inflation.

The Raise the Wage Act of 2017, which Sanders and Murray will unveil later today, would hike the minimum wage for the first time in a decade, raising it to $9.25 immediately, and inching it up to $15 by 2024, while simultaneously raising the minimum wage for tipped workers.

With Republicans in control of Congress, the bill is largely a messaging vehicle, with no chance of passage. But its support from the conference is the latest example of the Democratic Party’s leftward shift since the defeat of 2016 presidential nominee Hillary Clinton.

The last version of the Sanders bill, 2015’s Pay Workers a Living Wage Act, had just five co-sponsors. The new bill counts 22 co-sponsors, including Senate Democratic leader Chuck Schumer. Just two years ago, Schumer resisted the $15 minimum wage proposal, instead co-sponsoring Murray’s legislation for a $12 wage — “a winner issue for us,” according to Schumer.

To Democrats’ surprise, and occasional irritation, the size of the wage hike became a defining issue of the 2016 primaries. Clinton, like Schumer, backed a $12 minimum wage; Sanders chided her for not backing the higher number favored by the SEIU-backed “Fight for 15” movement.

“History has outpaced Secretary Clinton because all over this country people are standing up and saying $12 is not good enough,” Sanders said one year ago, at the final televised debate with Clinton in Brooklyn, N.Y.

Since then, Sanders has used his increased prominence on the left and around the Democratic Party to push for the higher wage. Wednesday’s legislation relies in part on the analysis of the progressive Economic Policy Institute, whose president, Larry Mishel, said in an interview that critics who warned that a higher wage would kill jobs were relying on outdated nostroms.

“They don’t know that, and if they insist on it, this will be the first time those people ever care about low-wage workers,” said Mishel. “It’s always odd to find the employers of low-wage workers claim to be the heroes of young black teenagers, who on any other day of the week they do everything they can to ignore them.”

David WeigelDavid Weigel is a national political correspondent covering Congress and grass-roots political movements. He is the author of "The Show That Never Ends," a history of progressive rock music. Follow